SUMMARY OF OBJECTIVES: Alcoholism is a common, heritable, multi-genic disease but it has so far proved difficult to map genes directly. Understanding the genetic origins of alcoholism may improve preventive measures and treatment. Low Voltage Alpha EEG and the P300 ERP have both been shown to be associated with alcoholism. The aim of this project is to collect these and other EEG phenotypes in 400 members of a Plains American Indian Tribe. These individuals come from several very large pedigrees. We already have psychiatric diagnoses and DNA on most tribal members and will complete this data set for the 400 individuals. We will then be in a position to perform transmission and linkage analysis for alcoholism in this tribe. The objectives of this contract are: to provide facilities for the EEG studies, to recruit the subjects and perform EEG and psychological testing (all under training and supervision by NIAAA staff), to collect and enter all data for analysis by NIAAA staff.